Taco Bell is under fire after a California employee took a picture of himself licking taco shells that were possibly sold to customers afterward. The picture, which was posted to Taco Bell’s Facebook page on Monday, is being investigated by the fast food chain. Taco Bell replied to the photo immediately, though they did not have it taken down.

“This sure says a lot about your employees, food treatment and what they post on the Internet," read the photo caption of the gross image, which was posted by J.J. O’Brien Nolan. It is unclear who the employee is, but he works in Ridgecrest, Calif.

“We have strict food handling procedures and zero tolerance for any violations,” the company responded on Facebook. “When we learned of the situation, we immediately contacted this restaurant’s leadership, and, although we believe it is a prank and the food was not served to customers, we are conducting a full-scale investigation and will be taking swift action against those involved.”

Cathy Marx, who manages the Taco Bell in that location, told CNBC, “We’re currently dealing with it.”

“Nothing is more important than the safety of our customers and team members, and we have strict food handling procedures and zero tolerance for any violations,” a company spokesman later said in a statement to the network.